EH Chapter 13: Cryptography

With a rotation of 4, what does erwaiv decrypt to?

answer

What do you call a message before it is encrypted?

Plain text

What does PGP use to verify identity?

Web of trust

What principle is used to demonstrate that a signed message came from the owner of the key that signed it?

Nonrepudiation

What is Diffie‐Hellman used for?

Key exchange

How did 3DES improve on DES?

Used three keys

What improvement does elliptic curve cryptography make?

Smaller keys improve speed

What is it called when two different data sets yield the same cryptographic hash?

Collision

Which of the following terms can be used in a description of asymmetric key encryption?

Public key

If Alice were to send an email to Bob, what key would she use to encrypt the message?

Public key

What property allows you to trust someone trusted by a certificate authority you trust?

Transitive property

Why is symmetric key encryption typically used over asymmetric key encryption?

It's faster.

What is it called when both symmetric and asymmetric keys are used?

Hybrid cryptosystem

What is MD5 or SHA‐1 commonly used for in cryptography?

Message authentication code (MAC)

What type of encryption does PGP use?

Asymmetric key

What tool would you use to identify ciphersuites in use on a web server?

sslscan

How does AES protect against related‐key attacks?

Implementation doesn't allow related keys

What is one advantage of using a certificate authority?

Trusted third party doing validation

How does a certificate authority keep a list of valid certificates up‐to‐date?

Certificate revocation lists

What security property suggests that an email signed by an individual's key must have come from that person?

Nonrepudiation